3 ms·

Of course, for most intents and purposes, it's "absolutely" true to say that there is no perpetual motion machines. But if we want to be precise, I don't think

Of course, for most intents and purposes, it's "absolutely" true to say that there is no perpetual motion machines. But if we want to be precise, I don't think we can escape the fact that this truth is "merely" relative to a specific conceptual framework. The now-deprecated conceptual frameworks of the past (religions & cie) weren't so decisive regarding perpetual motion machines for example. In religions/science, people had/have a tendency to think "we've reached the peek", but history relentlessly teaches us to be more careful. This point of view probably is pedantic, in the context of perpetual motion machines, but that mindset is so prevalent in society today that I can't think of it as a bad habit: it's easy to be blinded by knowledge as much as by ignorance.

jacquesm 3y ago
No, it's a simple matter of classification. Given a class of hypothetical devices 'X' with a strict and clear definition the question is whether or not device 'Y' is a member of said class. If it isn't then that's the end of that.
- mbivert 3y ago
  Fair enough. It's amusing given the context: I think you're using a precise definition of "perpetual (motion) machine", while I'm relying more on the one of an average human.
  - jacquesm 3y ago
    An average human would not be able to distinguish something that looks like a perpetual motion machine from something that actually is a perpetual motion machine. But it's fine to have different degrees of rigor for lay people than for scientists, the scientists have never been confused on this one, lay people obviously can be simply because the lack the relevant background. Just like 'really long' is not for ever and 'really large' is not infinite.
- dr_dshiv 3y ago
  Yes, but it is quite hard to define it precisely — which is partly why it was so astonishing then and now. For instance, to say: “a machine that operates indefinitely without the addition of fuel or energy” well, neither fuel nor energy is added to this machine, not in any apparent way. Instead, it absorbs the natural fluctuations of the surrounding environment and translates that to motive power. Now imagine that some huckster claimed to do that with “quantum zero point energy” or something, I think we’d treat the device like a perpetual motion machine — and look under the table for the trick. You’ll need to translate the page. It’s a fascinating story. Drebbel isn’t well known in the English speaking world — but he also designed the first cybernetic system, a thermostat. https://historiek.net/perpetuum-mobile-cornelis-drebbel/150502/ https://historiek.net/perpetuum-mobile-cornelis-drebbel/1505...
  - jacquesm 3y ago
    That's fair, the definition itself is difficult. What's interesting is that there is a never ending stream of would-be inventors of PMs that really believe in their devices no matter how easy it is to poke holes in the physics. Most of them don't begin to qualify for a closer examination (assuming they'd agree to that in the first place) and the few that do are often marvels of engineering and the inventors themselves don't actually know or realize how their devices work. I was part of an online community of renewable energy enthusiasts and we had more than our fair share of cranks there peddling their 'free energy', 'over unity' and 'perpetual motion' devices so I'm probably too bluntly dismissive of anybody that thinks they've finally got it. Usually they are clever engineers but they miss the physics theory. And if even the US patent office continues to fall for it who am I to complain... https://patents.google.com/patent/US6362718 https://patents.google.com/patent/US6362718

jacquesm 3y ago

No, it's a simple matter of classification. Given a class of hypothetical devices 'X' with a strict and clear definition the question is whether or not device 'Y' is a member of said class. If it isn't then that's the end of that.

mbivert 3y ago
Fair enough. It's amusing given the context: I think you're using a precise definition of "perpetual (motion) machine", while I'm relying more on the one of an average human.
- jacquesm 3y ago
  An average human would not be able to distinguish something that looks like a perpetual motion machine from something that actually is a perpetual motion machine. But it's fine to have different degrees of rigor for lay people than for scientists, the scientists have never been confused on this one, lay people obviously can be simply because the lack the relevant background. Just like 'really long' is not for ever and 'really large' is not infinite.
dr_dshiv 3y ago
Yes, but it is quite hard to define it precisely — which is partly why it was so astonishing then and now. For instance, to say: “a machine that operates indefinitely without the addition of fuel or energy” well, neither fuel nor energy is added to this machine, not in any apparent way. Instead, it absorbs the natural fluctuations of the surrounding environment and translates that to motive power. Now imagine that some huckster claimed to do that with “quantum zero point energy” or something, I think we’d treat the device like a perpetual motion machine — and look under the table for the trick. You’ll need to translate the page. It’s a fascinating story. Drebbel isn’t well known in the English speaking world — but he also designed the first cybernetic system, a thermostat. https://historiek.net/perpetuum-mobile-cornelis-drebbel/150502/ https://historiek.net/perpetuum-mobile-cornelis-drebbel/1505...
- jacquesm 3y ago
  That's fair, the definition itself is difficult. What's interesting is that there is a never ending stream of would-be inventors of PMs that really believe in their devices no matter how easy it is to poke holes in the physics. Most of them don't begin to qualify for a closer examination (assuming they'd agree to that in the first place) and the few that do are often marvels of engineering and the inventors themselves don't actually know or realize how their devices work. I was part of an online community of renewable energy enthusiasts and we had more than our fair share of cranks there peddling their 'free energy', 'over unity' and 'perpetual motion' devices so I'm probably too bluntly dismissive of anybody that thinks they've finally got it. Usually they are clever engineers but they miss the physics theory. And if even the US patent office continues to fall for it who am I to complain... https://patents.google.com/patent/US6362718 https://patents.google.com/patent/US6362718